Rationally designed protein A surface molecularly imprinted magnetic nanoparticles for the capture and detection of .

(), a commensal organism found on the human skin, is commonly associated with nosocomial infections and exhibits virulence mediated by toxins and resistance to antibiotics. The global threat of antibiotic resistance has necessitated antimicrobial stewardship to improve the safe and appropriate use of antimicrobials; hence, there is an urgent demand for the advanced, cost-effective, and rapid detection of specific bacteria. In this regard, we aimed to selectively detect using surface molecularly imprinted magnetic nanoparticles templated with a well-known biomarker protein A, specific to .

Greening the pathways: a comprehensive review of sustainable synthesis strategies for silica nanoparticles and their diverse applications.

Silica nanoparticles (SiNPs) have emerged as a multipurpose solution with wide-ranging applications in various industries such as medicine, agriculture, construction, cosmetics, and food production. In 1961, Stöber introduced a ground-breaking sol-gel method for synthesizing SiNPs, which carried a new era of exploration both in academia and industry, uncovering numerous possibilities for these simple yet multifaceted particles. Inspite of numerous reported literature with wide applicability, the synthesis of these nanoparticles with the desired size and functionalities poses considerable challenges.

A facile cost-effective electrolyte-assisted approach and comparative study towards the Greener synthesis of silica nanoparticles.

Nowadays, silica nanoparticles are gaining tremendous importance because of their wide applications across different domains such as drug delivery, chromatography, biosensors, and chemosensors. The synthesis of silica nanoparticles generally requires a high percentage composition of organic solvent in an alkali medium. The eco-friendly synthesis of silica nanoparticles in bulk amounts can help save the environment and is cost-effective.

COVID-19 Detection Using a 3D-Printed Micropipette Tip and a Smartphone.

The COVID-19 pandemic has caused over 7 million deaths worldwide and over 1 million deaths in the US as of October 15, 2022. Virus testing lags behind the level or availability necessary for pandemic events like COVID-19, especially in resource-limited settings. Here, we report a low cost, mix-and-read COVID-19 assay using a synthetic SARS-CoV-2 sensor, imaged and processed using a smartphone.

Bio-modified magnetic nanoparticles with Terminalia arjuna bark extract for the removal of methylene blue and lead (II) from simulated wastewater.

This study reports a greener, cheaper and convenient approach to synthesize Terminalia arjuna bark extract coated magnetite nanoparticles (TA@MNPs) using the co-precipitation method and efficient removal of methylene blue (MB) and lead ions [Pb(II)] from simulated wastewater. The synthesized nanoparticles (NPs) were characterized by various techniques such as DLS, XRD, FTIR, HRTEM, AGM, and TGA. From TGA analysis, TA@MNPs was found to be stable even after 500 °C.

Biomarker imprinted magnetic core-shell nanoparticles for rapid, culture free detection of pathogenic bacteria.

Rapid and selective detection of microorganisms in complex biological systems draws huge attention to address the rising issue of antimicrobial resistance. Diagnostics based on the identification of whole microorganisms are laborious, time-consuming and costly, thus alternative strategies for early clinical diagnosis include biomarker based microbial detection. This paper describes a low-cost, easy-to-use method for the detection of Pseudomonas aeruginosa infections by specifically identifying a biomarker pyocyanin, using surface-molecularly imprinted nanoparticles or "plastibodies".

Novel epoxy-silica nanoparticles to develop non-enzymatic colorimetric probe for analytical immuno/bioassays.

We have developed a novel method to develop epoxy silica nanoparticles (EfSiNP) in a single pot. High surface coverage of epoxy functional groups between 150 and 57000 molecules per particles (∼10-10 molecules/mL of 200 nm EfSiNPs) was achieved for different preparation conditions. We then created a red colored probe by conjugating Fuchsin dye to the epoxy functionalities of EfSINPs.

Automated 3D-Printed Microfluidic Array for Rapid Nanomaterial-Enhanced Detection of Multiple Proteins.

We report here the fabrication and validation of a novel 3D-printed, automated immunoarray to detect multiple proteins with ultralow detection limits. This low cost, miniature immunoarray employs electrochemiluminescent (ECL) detection measured with a CCD camera and employs touch-screen control of a micropump to facilitate automated use. The miniaturized array features prefilled reservoirs to deliver sample and reagents to a paper-thin pyrolytic graphite microwell detection chip to complete sandwich immunoassays.

Evaluating Metabolite-Related DNA Oxidation and Adduct Damage from Aryl Amines Using a Microfluidic ECL Array.

Damage to DNA from the metabolites of drugs and pollutants constitutes a major human toxicity pathway known as genotoxicity. Metabolites can react with metal ions and NADPH to oxidize DNA or participate in S2 reactions to form covalently linked adducts with DNA bases. Guanines are the main DNA oxidation sites, and 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG) is the initial product.

Albumin removal from human serum using surface nanopockets on silica-coated magnetic nanoparticles.

Selective removal of albumin from human serum is an essential step prior to proteomic analyses, especially when using mass spectrometry. Here we report stable synthetic nanopockets on magnetic nanoparticle surfaces that bind to human serum albumin (HSA) with high affinity and specificity. The nanopockets are created by templating HSA on 200 nm silica-coated paramagnetic nanoparticles using polymer layers made using 4 organo-silane monomers.

FeO nanoparticles on graphene oxide sheets for isolation and ultrasensitive amperometric detection of cancer biomarker proteins.

Ultrasensitive mediator-free electrochemical detection for biomarker proteins was achieved at low cost using a novel composite of FeO nanoparticles loaded onto graphene oxide (GO) nano-sheets (FeO@GO). This paramagnetic FeO@GO composite (1µm size range) was decorated with antibodies against prostate specific antigen (PSA) and prostate specific membrane antigen (PSMA), and then used to first capture these biomarkers and then deliver them to an 8-sensor detection chamber of a microfluidic immunoarray. Screen-printed carbon sensors coated with electrochemically reduced graphene oxide (ERGO) and a second set of antibodies selectively capture the biomarker-laden FeO@GO particles, which subsequently catalyze hydrogen peroxide reduction to detect PSA and PSMA.

Fast nucleation for silica nanoparticle synthesis using a sol-gel method.

We have developed a method that for the first time allowed us to synthesize silica particles in 20 minutes using a sol-gel preparation. Therefore, it is critically important to understand the synthesis mechanism and kinetic behavior in order to achieve a higher degree of fine tuning ability during the synthesis. In this study, we have employed our ability to modulate the physical nature of the reaction medium from sol-gel to emulsion, which has allowed us to halt the reaction at a particular time; this has allowed us to precisely understand the mechanism and chemistry of the silica polymerization.

Sodium hydroxide catalyzed monodispersed high surface area silica nanoparticles.

Understanding of the synthesis kinetics and our ability to modulate medium conditions allowed us to generate nanoparticles via an ultra-fast process. The synthesis medium is kept quite simple with tetraethyl orthosilicate (TEOS) as precursor and 50% ethanol and sodium hydroxide catalyst. Synthesis is performed under gentle conditions at 20 °C for 20 min Long synthesis time and catalyst-associated drawbacks are most crucial in silica nanoparticle synthesis.

Antibody-like Biorecognition Sites for Proteins from Surface Imprinting on Nanoparticles.

Natural antibodies are used widely for important applications such as biomedical analysis, cancer therapy, and directed drug delivery, but they are expensive and may have limited stability. This study describes synthesis of antibody-like binding sites by molecular imprinting on silica nanoparticles (SiNP) using a combination of four organosilane monomers with amino acid-like side chains providing hydrophobic, hydrophilic, and H-bonding interactions with target proteins. This approach provided artificial antibody (AA) nanoparticles with good selectivity and specificity to binding domains on target proteins in a relatively low-cost synthesis.

Resistive-Pulse Measurements with Nanopipettes: Detection of Vascular Endothelial Growth Factor C (VEGF-C) Using Antibody-Decorated Nanoparticles.

Quartz nanopipettes have recently been employed for resistive-pulse sensing of Au nanoparticles (AuNP) and nanoparticles with bound antibodies. The analytical signal in such experiments is the change in ionic current caused by the nanoparticle translocation through the pipette orifice. This paper describes resistive-pulse detection of cancer biomarker (Vascular Endothelial Growth Factor-C, VEGF-C) through the use of antibody-modified AuNPs and nanopipettes.

3D-Printed Fluidic Devices for Nanoparticle Preparation and Flow-Injection Amperometry Using Integrated Prussian Blue Nanoparticle-Modified Electrodes.

A consumer-grade fused filament fabrication (FFF) 3D printer was used to construct fluidic devices for nanoparticle preparation and electrochemical sensing. Devices were printed using poly(ethylene terephthalate) and featured threaded ports to connect polyetheretherketone (PEEK) tubing via printed fittings prepared from acrylonitrile butadiene styrene (ABS). These devices included channels designed to have 800 μm × 800 μm square cross sections and were semitransparent to allow visualization of the solution-filled channels.